en_tn/exo/01/06.md

all his brothers

this includes 10 older brothers and 1 younger brother

were fruitful

This means that the Israelite population grew quickly. AT: "had many children" or "gave birth to many children" (UDB). (See: rc://en/ta/man/translate/figs-idiom)

the land was filled with them

AT: "They filled the land" (See: rc://en/ta/man/translate/figs-activepassive)

with them

The word "them" refers to the Israelites.